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lattice-boltzmann-method
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Lattice Boltzmann method on quadtree grids for simulating fluid flow through porous media: A new automatic algorithm
, Article Physica A: Statistical Mechanics and its Applications ; Vol. 392, issue. 20 , May , 2013 , p. 4772-4786 ; ISSN: 03784371 ; Jamshidi, S ; Masihi, M ; Sharif University of Technology
Abstract
During the past two decades, the lattice Boltzmann (LB) method has been introduced as a class of computational fluid dynamic methods for fluid flow simulations. In this method, instead of solving the Navier Stocks equation, the Boltzmann equation is solved to simulate the flow of a fluid. This method was originally developed based on uniform grids. However, in order to model complex geometries such as porous media, it can be very slow in comparison with other techniques such as finite differences and finite elements. To eliminate this limitation, a number of studies have aimed to formulate the lattice Boltzmann on the unstructured grids. This paper deals with simulating fluid flow through a...
An investigation on the body force modeling in a lattice Boltzmann BGK simulation of generalized Newtonian fluids
, Article Physica A: Statistical Mechanics and its Applications ; Vol. 415, issue , 2014 , pp. 315-332 ; Manzari, M. T ; Sharif University of Technology
Abstract
Body force modeling is studied in the Generalized Newtonian (GN) fluid flow simulation using a single relaxation time lattice Boltzmann (LB) method. First, in a shear thickening Poiseuille flow, the necessity for studying body force modeling in the LB method is explained. Then, a parametric unified framework is constructed for the first time which is composed of a parametric LB model and its associated macroscopic dual equations in both steady state and transient simulations. This unified framework is used to compare the macroscopic behavior of different forcing models. Besides, using this unified framework, a new forcing model for steady state simulations is devised. Finally, by solving a...
A high-order compact finite-difference lattice Boltzmann method for simulation of steady and unsteady incompressible flows
, Article International Journal for Numerical Methods in Fluids ; Vol. 75, Issue. 10 , 2014 , Pages 713-746 ; ISSN: 02712091 ; Ezzatneshan, E ; Sharif University of Technology
Abstract
A high-order compact finite-difference lattice Boltzmann method (CFDLBM) is proposed and applied to accurately compute steady and unsteady incompressible flows. Herein, the spatial derivatives in the lattice Boltzmann equation are discretized by using the fourth-order compact FD scheme, and the temporal term is discretized with the fourth-order Runge-Kutta scheme to provide an accurate and efficient incompressible flow solver. A high-order spectral-type low-pass compact filter is used to stabilize the numerical solution. An iterative initialization procedure is presented and applied to generate consistent initial conditions for the simulation of unsteady flows. A sensitivity study is also...
Implementation of a high-order compact finite-difference lattice Boltzmann method in generalized curvilinear coordinates
, Article Journal of Computational Physics ; Vol. 267 , 2014 , Pages 28-49 ; ISSN: 00219991 ; Ezzatneshan, E ; Sharif University of Technology
Abstract
In this work, the implementation of a high-order compact finite-difference lattice Boltzmann method (CFDLBM) is performed in the generalized curvilinear coordinates to improve the computational efficiency of the solution algorithm to handle curved geometries with non-uniform grids. The incompressible form of the discrete Boltzmann equation with the Bhatnagar-Gross-Krook (BGK) approximation with the pressure as the independent dynamic variable is transformed into the generalized curvilinear coordinates. Herein, the spatial derivatives in the resulting lattice Boltzmann (LB) equation in the computational plane are discretized by using the fourth-order compact finite-difference scheme and the...
Comparison of boundary slip for two variants of immersed boundary method in lattice Boltzmann framework
, Article Physica A: Statistical Mechanics and its Applications ; Vol. 404 , 2014 , Pages 200-216 ; ISSN: 03784371 ; Manzari, M. T ; Sharif University of Technology
Abstract
In this paper, the Immersed Moving Boundary-Lattice Boltzmann (IMB-LB) method is compared with the single relaxation time and multiple-relaxation-time versions of the Immersed Boundary-Lattice Boltzmann (IB-LB) method in terms of the amount of numerical velocity slip produced on solid boundaries. The comparisons are performed for both straight and curved boundaries based on the effects of thickness of virtual domain used in the IB method for the first time, and relaxation time parameter(s) of the LB method. For the straight boundaries, a shear flow problem is studied while for the curved boundaries, a falling circular cylinder in an infinite channel is investigated. First, sensitivities of...
LBM simulation of electro-osmotic flow (EOF) in nano/micro scales porous media with an inclusive parameters study
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) ; Vol. 7 , November , 2014 ; ISBN: 9780791849545 ; Lee, E. S ; Salimi, M. R ; Sharif University of Technology
Abstract
In this paper, we present our results about simulation of 2D-EOF in Nano/Micro scales porous media using lattice Boltzmann method (LBM) in micro-channel for EOF. The high efficient numerical code use strongly high nonlinear Poisson Boltzmann equation to predicate behavior of EOF in complex geometry. The results are developed with precisely investigation of several effective parameters on permeability of EOF, such as geometry (channel height and number and location of charge), external electric field, thickness of Debye length (ionic concentration), and zeta potential. Our results are in excellent agreement with available analytical results. Our results show that for certain external electric...
Lattice Boltzmann method for simulating impulsive water waves generated by landslides
, Article Scientia Iranica ; Vol. 21, issue. 2 , 2014 , p. 318-328 ; 1026-3098 ; Sarfaraz, M ; Sharif University of Technology
Abstract
Impulsive water waves generated by landslides impose severe damage on coastal areas. Very large mass ows in the ocean can generate catastrophic tsunamis. Preventing damage to dams and coastal structures, and saving the lives of local people against landslide-generated waves, has become an increasingly important issue in recent years. Numerical modeling of landslide-generated waves is a challenging subject in CFD. The reason lies in the difficulty of determining the interaction between the moving solids and sea water, which causes complicated turbulent regimes around the moving mass and at the water surface. Submarine or aerial types of landslide can further complicate the problem. Up to now,...
Lattice Boltzmann method on quadtree grids for simulating fluid flow through porous media: A new automatic algorithm
, Article Physica A: Statistical Mechanics and its Applications ; Volume 392, Issue 20 , 2013 , Pages 4772-4786 ; 03784371 (ISSN) ; Jamshidi, S ; Masihi, M ; Sharif University of Technology
2013
Abstract
During the past two decades, the lattice Boltzmann (LB) method has been introduced as a class of computational fluid dynamic methods for fluid flow simulations. In this method, instead of solving the Navier Stocks equation, the Boltzmann equation is solved to simulate the flow of a fluid. This method was originally developed based on uniform grids. However, in order to model complex geometries such as porous media, it can be very slow in comparison with other techniques such as finite differences and finite elements. To eliminate this limitation, a number of studies have aimed to formulate the lattice Boltzmann on the unstructured grids. This paper deals with simulating fluid flow through a...
Investigation of flow around a confined elliptical cylinder using the Lattice Boltzmann method
, Article Middle East Journal of Scientific Research ; Volume 15, Issue 1 , 2013 , Pages 8-13 ; 19909233 (ISSN) ; Esfahanian, V ; Salari, M ; Sharif University of Technology
2013
Abstract
This paper deals with the investigation of the laminar flow past an elliptical cylinder confined in a channel. In this paper, the Lattice Boltzmann (LB) method is used to simulate flow in two dimensions. The present LB method with the used boundary conditions is validated in simulations of the incompressible flow past a circular cylinder. The simulations are carried out in a range of condition, 0≤θ≤90 (angle of incidence), 5≤Re≤100, (Reynolds number) for AR=0.25,0.5 (aspect ratio). The effects of those parameters on the drag and lift coefficients and other flow characteristics of the cylinder are examined in detail. The results demonstrate that the drag and lift coefficients increase with...
Investigation of flow around a confined elliptical cylinder using the Lattice Boltzmann method
, Article World Applied Sciences Journal ; Volume 22, Issue 7 , 2013 , Pages 1013-1018 ; 18184952 (ISSN) ; Salari, M ; Esfahanian, V ; Sharif University of Technology
2013
Abstract
This paper deals with the investigation of the laminar flow past an elliptical cylinder confined in a channel. In this paper, the Lattice Boltzmann (LB) method is used to simulate flow in two dimensions. The present LB method with the used boundary conditions is validated in simulations of the incompressible flow past a circular cylinder. The simulations are carried out in a range of condition, 0 90 (angle of incidence), 5 Re 100, (Reynolds number) for AR=0.25,0.5 (aspect ratio). The effects of those parameters on the drag and lift coefficients and other flow characteristics of the cylinder are examined in detail. The results demonstrate that the drag and lift coefficients increase with the...
Effects of various parameters on the coating of substrates with trenches
, Article 2012 International Conference on Advanced Materials Design and Mechanics, ICAMDM 2012, Xiamen, 5 June 2012 through 7 June 2012 ; Volume 569 , 2012 , Pages 219-222 ; 10226680 (ISSN) ; 9783037854808 (ISBN) ; Moosavi, A ; Sharif University of Technology
2012
Abstract
We investigate thin liquid film coating of substrates with trenches via lattice Boltzmann method. The effects of different parameters such as the capillary number, the contact angles and geometric parameters on the results are studied. Our results indicate that for trench depths greater than a critical size coating of the trench is not successful. The critical depth increases by decreasing the capillary number. Moreover we find height, width, capillary number and contact angle under which the coating is successful. The results have been compared with the available results and very close agreement has been achieved
The dynamics of wettability driven droplets in smooth and corrugated microchannels
, Article Journal of Statistical Mechanics: Theory and Experiment ; Volume 2012, Issue 10 , 2012 ; 17425468 (ISSN) ; Moosavi, A ; Mazloomi, A ; Sharif University of Technology
IOP
2012
Abstract
A multi-component lattice Boltzmann scheme is used to investigate the dynamics of a wettability driven droplet within a microchannel. The driving force for the motion is created by a stepwise change in the wettability of the channel walls. Moreover, an analytical solution is developed for evaluation of the dynamics of the droplet inside the channel. The effects of various parameters such as the height of the channel, the wetting pattern of the channel walls, the viscosity and the density ratio on the dynamics are studied. Also, the effect of grooves of different sizes on the channel surfaces on the dynamics of the droplet is investigated for both hydrophilic and hydrophobic surfaces....
Investigation of particle dispersion and deposition in a channel with elliptic obstructions using lattice Boltzmann method
, Article 2012 7th IEEE International Conference on Nano/Micro Engineered and Molecular Systems, NEMS 2012, 5 March 2012 through 8 March 2012 ; March , 2012 , Pages 523-528 ; 9781467311243 (ISBN) ; Moosavi, A ; Sharif University of Technology
2012
Abstract
Particle transport and deposition in a channel flow with elliptic obstruction is studied. Numerical simulation of fluid flow is performed using two-dimensional lattice Boltzmann method, while one-way coupling Lagrangian method for particle tracking is used. Standard particles are injected in the inlet of the channel. Gravity, Drag force, Brownian forces, and the Saffman lift are considered in equation of particle motion. The influence of geometrical parameter, ellipse aspect ratio, is studied on dispersion and deposition of particles as well as the flow parameters, such as Reynolds number. In addition, the effect of particles size -particles of 0.01-10μm in diameter- on dispersion and...
Coupled lattice boltzmann - Discrete element method for numerical modelling of sand production
, Article Particle-Based Methods II - Fundamentals and Applications, 26 October 2011 through 28 October 2011 ; 2011 , Pages 371-382 ; 9788489925670 (ISBN) ; Pak, A ; Sharif University of Technology
Abstract
In this study, a coupled numerical approach based on Lattice Boltzmann Method (LBM) and Discrete Element Method (DEM) is employed for 2D simulation of fluid flow in porous media comprising of movable circular particles. The developed model is used for simulation of sand production which is one of the important problems in petroleum industry. The numerical tool has proved to have the capability of investigating the mechanisms involved in sand production problem. The results show that the rate of sand production is strongly affected by flow rate and confining pressure
Pore scale study of permeability and tortuosity for flow through particulate media using Lattice Boltzmann method
, Article International Journal for Numerical and Analytical Methods in Geomechanics ; Volume 35, Issue 8 , 2011 , Pages 886-901 ; 03639061 (ISSN) ; Pak, A ; Sharif University of Technology
2011
Abstract
In this paper, Lattice Boltzmann method (LBM) has been used to study the effects of permeability and tortuosity on flow through saturated particulate media and identify the relationships between permeability and tortuosity with other parameters such as particles diameter, grain specific surface, and porosity. LBM is a simple kinematic model that can incorporate the essential physics of microscopic and mesoscopic processes involved in flow through granular soils. The obtained results indicate that the 2D LB model, due to its inherent theoretical advantages, is capable of demonstrating that the porosity and specific surface are the most influential parameters in determining the intrinsic...
Numerical study of factors influencing relative permeabilities of two immiscible fluids flowing through porous media using lattice Boltzmann method
, Article Journal of Petroleum Science and Engineering ; Volume 77, Issue 1 , 2011 , Pages 135-145 ; 09204105 (ISSN) ; Pak, A ; Sharif University of Technology
Abstract
Relative permeability curves have practical implications in petroleum reservoir simulations. Study of the effects of reservoir wettability, pore shape geometry, and viscosity ratio of flowing fluids on the relative permeabilities is of great importance in reservoir modeling. In this paper, lattice Boltzmann method (LBM) is employed for analyzing the two-fluid flow in rigid porous media. The developed LBM code proved to be a robust numerical tool for analyzing the factors that influence the relative permeabilities of two immiscible fluids flowing through porous media. The numerically derived relative permeability curves demonstrate that in neutrally wet reservoirs, the effect of viscosity...
Simulation of buoyant bubble motion in viscous flows employing lattice Boltzmann and level set methods
, Article Scientia Iranica ; Volume 18, Issue 2 B , 2011 , Pages 231-240 ; 10263098 (ISSN) ; Hannani, S. K ; Sharif University of Technology
2011
Abstract
Recently, a hybrid Lattice Boltzmann Level Set Method (LBLSM) for two-phase incompressible fluids with large density differences, in cases of negligible or a priori known pressure gradients, has been proposed. In the present work, the mentioned LBLSM method is extended to take into account pressure gradient effects. The lattice Boltzmann method is used for calculating velocities, the interface is captured by the level set function, and the surface tension is replaced by an equivalent body force. The method can be applied to simulate two-phase fluid flows with density ratios up to 1000 and viscosity ratios up to 100. In order to validate the method, the evolution and merging of rising bubbles...
Numerical simulation of sand production experiment using a coupled Lattice Boltzmann-Discrete Element Method
, Article Journal of Petroleum Science and Engineering ; Volume 135 , November , 2015 , Pages 218-231 ; 09204105 (ISSN) ; Pak, A ; Sharif University of Technology
Elsevier
2015
Abstract
In this study, a coupled numerical approach based on Lattice Boltzmann Method (LBM) and Discrete Element Method (DEM) is employed for two-dimensional simulation of fluid flow in deformable particulate media comprising of movable circular particles. The developed LB-DE code is validated against the results of a bi-axial shear test as well as two well-known benchmark problems including settling of a circular particle under gravity force inside a viscous fluid, and motion of a neutrally buoyant particle released in a Poiseuille flow. The verified code is then utilized for simulation of "Sand Production" phenomenon which is of importance for oil producing wells in weakly cemented sandstone...
Simulation of Two-Fluid Flow Through Particlulate Porous Media Contaning Moving Particles at Pore Scale Using Combined LB-DE Method
, Ph.D. Dissertation Sharif University of Technology ; Pak, Ali (Supervisor)
Abstract
A considerable number of engineering applications deal with flow of fluid(s) through particulate porous media. For certain engineering problems, fluid flow may displace and even dislodge the solid particles from the mass where a fluid-particle flow occurs. The complexity of involving processes which should be studied at the scale of moving particles transforms the analyses of these problems towards a difficult engineering task. Characteristics of solid grains such as size and shape and properties of the flowing fluid(s) such as viscosity and surface tension play essential roles in the behavior of fluid-particle systems. Also, when fluid flows through porous media, secondary processes such as...
Numerical Investigation of Nano-Particles Dispersion and Deposition in Curved and Bifurcating Channels using Lattice Boltzmann Method
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor)
Abstract
Investigation of transport and deposition of aerosol particles attracts interests in many fields of sciences. Various numerical and computational methods has been utilized in particulate flows studies. In recent relevant researches lattice Boltzmann method has been widely used and is reported to be a robust and efficient method. In present study, numerical investigation of dispersion and deposition of aerosol particles is performed in curved and bifurcating channels using LBM. Fluid flow simulations are performed using LBM while one-way coupling Lagrangian point of view is used for particle tracking. As the first showcase, transport and deposition of aerosol particles in channel flow with...